The objective of this study was to examine the degradation of short peptides corresponding to modified fragments of human growth hormone-releasing hormone by trypsin. Six analogues of pentapeptide 9-13 of human growth hormone-releasing hormone containing homoarginine, ornithine, glutamic acid, glycine, leucine or phenylalanine residue in position 11, two analogues of hexapeptide 8-13 of human growth hormone-releasing hormone and two analogues of heptapeptide 7-13 of human growth hormone-releasing hormone containing homoarginine or glycine residue in position 11 were obtained. The peptides were subjected to digestion by trypsin and the course of reaction was monitored using HPLC. It was found that the rate of hydrolysis of the Lys(12)-Val(13) peptide bond depends on the amino-acid residue preceding Lys(12). The extension of the peptide chain towards the N-terminus by introduction of consecutive amino-acid residues corresponding to the human growth hormone-releasing hormone sequence accelerates the hydrolysis process. These results may be of assistance in designing new analogues of human growth hormone-releasing hormone, more resistant to the activity of proteolytic enzymes.
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Invest Ophthalmol Vis Sci
January 2025
John F. Hardesty, MD, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine in St. Louis, St. Louis, Missouri, United States.
Ever since the US Food and Drug Administration (FDA) approved the first vascular endothelial growth factor (VEGF) antagonist 2 decades ago, inhibitors of VEGF have revolutionized the treatment of a variety of ocular disorders involving pathologic neovascularization and retinal exudation. In this perspective, we evaluate the current status of anti-VEGF therapies and the real-world challenges encountered with maintaining therapeutic outcomes. Finally, we describe novel VEGF-based and combinatorial approaches that are in clinical development.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
January 2025
Vitreous Retina Macula Consultants of New York, New York, United States.
Purpose: The purpose of this study was to develop ground-truth histology about contributors to variable fundus autofluorescence (FAF) signal and thus inform patient selection for treating geographic atrophy (GA) in age-related macular degeneration (AMD).
Methods: One woman with bilateral multifocal GA, foveal sparing, and thick choroids underwent 535 to 580 nm excitation FAF in 6 clinic visits (11 to 6 years before death). The left eye was preserved 5 hours after death.
Hepatol Int
January 2025
National Clinical Research Center for Digestive Disease, State Key Lab of Digestive Health, Beijing Friendship Hospital, Capital Medical University, Beijing, China.
Background: Our previous research demonstrated that growth differentiation factor 15 (GDF15) exhibited superior predictive capability for metabolic dysfunction-associated steatohepatitis (MASH) development with an AUC of 0.86 at 10 years before disease diagnosis. However, the specific pathways and molecular mechanisms associated with GDF15 expression during MASH development remain to be fully investigated in humans.
View Article and Find Full Text PDFCell Regen
January 2025
Department of Neurology, Zhongshan Hospital, Institute for Translational Brain Research, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200032, China.
The cultivation and differentiation of human embryonic stem cells (hESCs) into organoids are crucial for advancing of new drug development and personalized cell therapies. Despite establishing of chemically defined hESC culture media over the past decade, these media's reliance on growth factors, which are costly and prone to degradation, poses a challenge for sustained and stable cell culture. Here, we introduce an hESC culture system(E6Bs) that facilitates the long-term, genetically stable expansion of hESCs, enabling cells to consistently sustain high levels of pluripotency markers, including NANOG, SOX2, TRA-1-60, and SSEA4, across extended periods.
View Article and Find Full Text PDFOdontology
January 2025
Department of Periodontology, Faculty of Dentistry, Gazi University, Ankara, Turkey.
We aimed to investigate the wound-healing, antioxidant, and anti-inflammatory effects of pterostilbene (PTS) on human gingival fibroblasts (GF). Different concentrations of PTS were applied to GFs and cell viability was evaluated by MTT assay. GFs were stimulated by lipopolysaccharide (LPS) and the study groups were determined as LPS, LPS + 1 μM PTS, LPS + 10 μM PTS, and control.
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